Any pics of bulges. In underwear or whatever!
welcome to 4chan, anon. you can reply to posts by clicking the post number, or in this case you could just say OP's picture. Also, before asking for a source you should always right click the image and click 'search google for this image', and if that doesn't turn up a source then check saucenao, which is a more powerful version of the same thing.
link from saucenao: http://www.pixiv.net/member_illust.php?mode=medium&illust_id=45213044
sorry for the random lesson, it's just that random sauce requests annoy some people on here, and the more of them we avoid the more we keep the focus on porn.